Substrate processing method, manufacturing method of semiconductor device, program, and substrate processing apparatus

Abstract

To provide a technique capable of suppressing desorption of a predetermined element during film formation and maintaining the predetermined element in a film at a desired composition ratio.SOLUTION: A substrate processing method includes the steps of: (a) supplying a first gas containing a first element and a halogen element to a substrate; (b) supplying a second gas containing a second element different from the first element and hydrogen to the substrate; (c) supplying a plasma-excited hydrogen-containing gas different from the second gas to the substrate; and (d) supplying a third gas containing a third element different from the first element and the second element to the substrate. A cycle in which the (c) is performed after the (a) and the (b) and before the (d) is performed a predetermined number of times to form a film containing the first element, the second element, and the third element on the substrate.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a substrate processing method, a semiconductor device manufacturing method, a program, and a substrate processing apparatus. [Background technology]

[0002] BACKGROUND ART As one step in the manufacturing process of a semiconductor device, a process of supplying a predetermined gas to a substrate to form a film on the substrate is sometimes performed (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-153825 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a technique that can suppress the desorption of predetermined elements during film formation and maintain the predetermined elements in the film at a desired composition ratio. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, (a) supplying a first gas containing a first element and a halogen element to a substrate; (b) supplying a second gas containing a second element different from the first element and hydrogen to the substrate; (c) supplying a plasma-excited hydrogen-containing gas different from the second gas to the substrate; (d) supplying a third gas containing a third element different from the first element and the second element to the substrate; and performing a predetermined number of cycles in which (c) is performed after (a) and (b) and before (d), thereby forming a film containing the first element, the second element, and the third element on the substrate. [Effects of the Invention]

[0006] According to the present disclosure, it is possible to provide a technique that can suppress the desorption of predetermined elements during film formation and maintain the predetermined elements in the film at a desired composition ratio. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus suitably used in one embodiment of the present disclosure, showing a processing furnace 202 portion in vertical cross section. [Figure 2] FIG. 2 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus suitably used in one embodiment of the present disclosure, and is a cross-sectional view of the processing furnace 202 taken along line AA in FIG. [Figure 3] Fig. 3(a) is a perspective view of electrodes 300-1 and 300-2 preferably used in one embodiment of the present disclosure, when they are installed on an electrode fixture 301. Fig. 3(b) is a diagram showing the positional relationship between a heater 207 preferably used in one embodiment of the present disclosure, the electrode fixture 301, the electrodes 300-1 and 300-2, protrusions 310 for fixing the electrodes 300-1 and 300-2, and a reaction tube 203. [Figure 4] FIG. 4 is a schematic configuration diagram of a controller 121 of a substrate processing apparatus suitably used in one embodiment of the present disclosure, and is a block diagram showing a control system of the controller 121. [Figure 5] FIG. 5 is a diagram illustrating an example of a processing sequence according to an embodiment of the present disclosure. [Figure 6]Figure 6(a) is a diagram showing the state after steps A and B are performed, in which a portion of the second gas is bonded to the dangling bonds of the first element; Figure 6(b) is a diagram showing that in step C, impurities such as halogen elements bonded to the first element and hydrogen elements bonded to the second element are detached, and the bonds between the first element and the second element are increased; and Figure 6(c) is a diagram showing that as step C progresses further, the bonds between the first element and the second element are further increased. [Figure 7] FIG. 7 shows the measurement results of the film formed on the substrate. DETAILED DESCRIPTION OF THE INVENTION

[0008] <One aspect of the present disclosure> The first embodiment of the present disclosure will be described below mainly with reference to Figures 1 to 6. Note that the drawings used in the following description are all schematic, and the dimensional relationships between elements, the ratios of elements, etc. shown in the drawings do not necessarily match those in reality. Furthermore, the dimensional relationships between elements, the ratios of elements, etc. do not necessarily match between multiple drawings.

[0009] (heating device) (1) Configuration of the substrate processing equipment 1, the processing furnace 202 has a heater 207 as a temperature regulator (heating unit). The heater 207 is cylindrical and is installed vertically by being supported by a holding plate. The heater 207 also functions as an activation mechanism (thermal excitation unit) that thermally activates (excites) the gas.

[0010] An electrode fixture 301 (described later) is disposed inside the heater 207, and an electrode 300 (described later) of the plasma generating unit is disposed inside the electrode fixture 301. A reaction tube 203 is disposed concentrically with the heater 207 inside the electrode 300. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC), and has a cylindrical shape with a closed upper end and an open lower end. A manifold 209 is disposed concentrically below the reaction tube 203. The manifold 209 has a cylindrical shape with open upper and lower ends. The upper end of the manifold 209 engages with the lower end of the reaction tube 203 to support the reaction tube 203. An O-ring 220a is provided between the manifold 209 and the reaction tube 203 as a sealing member. A processing vessel (reaction vessel) is mainly composed of a reaction tube 203 and a manifold 209. A processing chamber 201 is formed in the cylindrical hollow portion of the processing vessel. The processing chamber 201 is configured to be able to accommodate a plurality of wafers 200 as substrates. Note that the processing vessel is not limited to the above configuration, and in some cases only the reaction tube 203 is referred to as the processing vessel.

[0011] (Gas supply section) Nozzles 249a and 249b serving as first and second supply units are provided in the processing chamber 201, respectively, so as to penetrate the sidewall of the manifold 209. The nozzles 249a and 249b are also referred to as the first nozzle and the second nozzle, respectively. The nozzles 249a and 249b are made of a heat-resistant material such as quartz or SiC. Gas supply pipes 232a and 232b are connected to the nozzles 249a and 249b, respectively. In this specification, the nozzles 249a and 249b are also referred to as R1 and R2, respectively.

[0012] Gas supply pipes 232a and 232b are respectively provided with mass flow controllers (MFCs) 241a and 241b, which are flow rate control devices (flow rate control parts), and valves 243a and 243b, which are on-off valves, in order from the upstream side of the gas flow. Gas supply pipes 232c and 232f are respectively connected to gas supply pipe 232a downstream of valve 243a. Gas supply pipes 232d, 232e, and 232g are respectively connected to gas supply pipe 232b downstream of MFC 241b. Gas supply pipes 232c to 232g are respectively provided with MFCs 241c to 241g and valves 243c to 243g in order from the upstream side of the gas flow.

[0013] As shown in FIGS. 1 and 2, the nozzles 249a and 249b are respectively provided in an annular space between the inner wall of the reaction tube 203 and the wafers 200 in a plan view, extending from the lower portion to the upper portion of the inner wall of the reaction tube 203 and rising upward in the loading direction (vertical direction) of the wafers 200. That is, the nozzles 249a and 249b are respectively provided on the sides of the edges (peripheral portions) of the wafers 200 loaded into the processing chamber 201 and perpendicular to the surfaces (flat surfaces) of the wafers 200. Gas supply holes 250a and 250b for supplying gas are respectively provided on the side surfaces of the nozzles 249a and 249b. The gas supply hole 250a opens toward the center of the reaction tube 203, enabling gas to be supplied toward the wafers 200. A plurality of the gas supply holes 250a and 250b are respectively provided from the lower portion to the upper portion of the reaction tube 203.

[0014] In this embodiment, gas is delivered via nozzles 249a and 249b arranged in a vertically elongated space that is annular in plan view and defined by the inner wall of the sidewall of the reaction tube 203 and the edges (peripheral portions) of the multiple wafers 200 arranged in the reaction tube 203, i.e., a cylindrical space. Gas is first ejected into the reaction tube 203 near the wafers 200 from gas supply holes 250a and 250b opened in the nozzles 249a and 249b, respectively. The main flow of gas in the reaction tube 203 is parallel to the surfaces of the wafers 200, i.e., horizontally. The gas that has flowed over the surfaces of the wafers 200, i.e., the residual gas after the reaction, flows toward the exhaust port, i.e., toward the exhaust pipe 231 described below.

[0015] A first gas containing a first element and a halogen element is supplied from the gas supply pipe 232a into the processing chamber 201 via the MFC 241a, the valve 243a, and the nozzle 249a.

[0016] A second gas containing a second element different from the first element and hydrogen (H) is supplied from the gas supply pipe 232b into the processing chamber 201 via the MFC 241b, the valve 243b, and the nozzle 249b.

[0017] From the gas supply pipes 232c and 232d, a H-containing gas different from the second gas is supplied into the processing chamber 201 via the MFCs 241c and 241d, the valves 243c and 243d, the gas supply pipes 232a and 232b, and the nozzles 249a and 249b.

[0018] A third gas containing a third element different from the first element and the second element is supplied from the gas supply pipe 232e into the processing chamber 201 via the MFC 241e, the valve 243e, the gas supply pipe 232b, and the nozzle 249b.

[0019] Inert gas is supplied from the gas supply pipes 232f and 232g into the processing chamber 201 via the MFCs 241f and 241g, the valves 243f and 243g, the gas supply pipes 232a and 232b, and the nozzles 249a and 249b, respectively. The inert gas acts as a purge gas, a carrier gas, a dilution gas, etc.

[0020] The first gas supply system mainly includes the gas supply pipe 232a, the MFC 241a, and the valve 243a. The second gas supply system mainly includes the gas supply pipe 232b, the MFC 241b, and the valve 243b. The hydrogen-containing gas supply system mainly includes the gas supply pipes 232c and 232d, the MFCs 241c and 241d, and the valves 243c and 243d. The third gas supply system mainly includes the gas supply pipe 232e, the MFC 241e, and the valve 243e. The inert gas supply system mainly includes the gas supply pipes 232f and 232g, the MFCs 241f and 241g, and the valves 243f and 243g.

[0021] (Board support) 1, a boat 217 serving as a substrate support is configured to support a plurality of wafers 200, for example, 25 to 200 wafers 200, in multiple stages, in a horizontal position, with their centers aligned in the vertical direction, i.e., arranged at intervals. The boat 217 is made of a heat-resistant material such as quartz or SiC. A heat insulating plate 218, also made of a heat-resistant material such as quartz or SiC, is supported in multiple stages at the bottom of the boat 217.

[0022] (Plasma generation unit) Next, the plasma generating section will be described with reference to FIGS.

[0023] An electrode 300 for generating plasma is provided outside the reaction tube 203 (processing vessel), i.e., on the outside (outer periphery) of the processing chamber 201. By applying power to the electrode 300, it is possible to convert gas into plasma and excite it inside the reaction tube 203, i.e., inside the processing chamber 201, i.e., to excite the gas into a plasma state. Hereinafter, the excitation of gas into a plasma state may be simply referred to as plasma excitation. The electrode 300 is configured to generate capacitively coupled plasma (CCP) inside the reaction tube 203 (processing vessel), i.e., inside the processing chamber 201, by applying high-frequency power (RF power).

[0024] Specifically, as shown in FIG. 2, an electrode 300 and an electrode fixture 301 for fixing the electrode 300 are disposed between the heater 207 and the reaction tube 203 .

[0025] 1 and 2, the electrode 300 and the electrode fixture 301 are provided in a space having an annular shape in plan view between the inner wall of the heater 207 and the outer wall of the reaction tube 203, and extend from the lower part to the upper part of the outer wall of the reaction tube 203 in the arrangement direction of the wafers 200. The electrode 300 is provided parallel to the nozzles 249a and 249b. The electrode 300 and the electrode fixture 301 are arranged and disposed concentrically with the reaction tube 203 and the heater 207 in plan view, but are not in contact with the heater 207.

[0026] As shown in Fig. 2, a plurality of electrodes 300 are provided, and these plurality of electrodes 300 are fixed to the inner wall of an electrode fixing device 301. More specifically, the inner wall surface of the electrode fixing device 301 is provided with protrusions (hooks) 310 onto which the electrodes 300 can be hooked, and the electrodes 300 are provided with openings 305, which are through-holes into which the protrusions 310 can be inserted. By hooking the electrodes 300 onto the protrusions 310 provided on the inner wall surface of the electrode fixing device 301 via the openings 305, the electrodes 300 can be fixed to the electrode fixing device 301. Note that Fig. 2 shows an example in which nine electrodes 300 are fixed to one electrode fixing device 301, and this configuration (unit) is composed of two sets, and Figs. 3(a) and 3(b) show an example of a configuration (unit) in which eight electrodes 300-1 and 300-2 are fixed to one electrode fixing device 301.

[0027] As shown in FIGS. 2 and 3(a), the electrode 300 includes a first electrode 300-1 and a second electrode 300-2. The first electrode 300-1 is connected to a high-frequency power supply (RF power supply) 320 via a matching box 325, and an arbitrary potential is applied to the first electrode 300-1. The second electrode 300-2 is grounded to the earth and serves as a reference potential (0 V). The first electrode 300-1 and the second electrode 300-2 are each configured as a plate-like member having a rectangular shape when viewed from the front. FIGS. 2, 3(a), and 3(b) show an example in which a plurality of first electrodes 300-1 and a plurality of second electrodes 300-2 are provided. FIGS. 3(a) and 3(b) show an example in which four first electrodes 300-1 and four second electrodes 300-2 are provided. By applying RF power between the first electrode 300-1 and the second electrode 300-2 from the RF power supply 320, plasma is generated in the region between the first electrode 300-1 and the second electrode 300-2. This region is also referred to as the plasma generation region. As shown in Fig. 2, the electrodes 300 (first electrode 300-1, second electrode 300-2) are arranged on an arc in a plan view and are equally spaced apart, i.e., the distances (gaps) between adjacent first electrodes 300-1 and second electrodes 300-2 are equal.

[0028] A high frequency of, for example, 25 MHz or more and 35 MHz or less is input to the electrode 300 from an RF power supply 320, thereby generating plasma (active species) 302 in the reaction tube 203. The plasma thus generated can supply the plasma 302 for substrate processing to the surface of the wafer 200 from the periphery of the wafer 200.

[0029] The electrode 300 mainly constitutes a plasma generating unit (plasma excitation unit (excitation unit), plasma activation mechanism) that excites (activates) the gas into a plasma state. The electrode fixture 301, matching box 325, and RF power supply 320 may be considered to be included in the plasma generating unit.

[0030] (Exhaust section) As shown in FIG. 1 , the reaction tube 203 is provided with an exhaust pipe 231 for exhausting the atmosphere inside the processing chamber 201. The exhaust pipe 231 is connected to a vacuum pump 246 as a vacuum exhaust device via a pressure sensor 245 as a pressure detector (pressure detection unit) that detects the pressure inside the processing chamber 201 and an APC (Auto Pressure Controller) valve 244 as an exhaust valve (pressure adjustment unit). The APC valve 244 is configured to evacuate and stop the evacuation of the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is operating. Furthermore, while the vacuum pump 246 is operating, the APC valve 244 is configured to adjust the pressure inside the processing chamber 201 by adjusting the valve opening based on pressure information detected by the pressure sensor 245. An exhaust system is mainly composed of the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 may be considered to be included in the exhaust system.

[0031] (Peripheral devices) A seal cap 219 serving as a furnace port cover capable of airtightly closing the lower end opening of the manifold 209 is provided below the manifold 209. An O-ring 220b serving as a seal member that comes into contact with the lower end of the manifold 209 is provided on the upper surface of the seal cap 219.

[0032] A rotation mechanism 267 for rotating the boat 217 is installed on the opposite side of the seal cap 219 from the processing chamber 201. A rotation shaft 255 of the rotation mechanism 267 passes through the seal cap 219 and is connected to the boat 217. The rotation mechanism 267 is configured to rotate the boat 217, thereby rotating the wafers 200. A boat elevator 115 serving as a lifting mechanism is configured to lift and lower the seal cap 219, thereby enabling the boat 217 to be loaded into and unloaded from the processing chamber 201.

[0033] The boat elevator 115 is configured as a transfer device (transfer mechanism) that transfers the boat 217, i.e., the wafers 200, into and out of the process chamber 201. Also, below the manifold 209, a shutter 219s is provided as a furnace port cover that can airtightly close the lower end opening of the manifold 209 while the seal cap 219 is being lowered by the boat elevator 115. An O-ring 220c is provided on the upper surface of the shutter 219s as a sealing member that abuts against the lower end of the manifold 209. The opening and closing operation (lifting and lowering operation, rotating operation, etc.) of the shutter 219s is controlled by a shutter opening and closing mechanism 115s.

[0034] A temperature sensor 263 serving as a temperature detector is installed inside the reaction tube 203. By adjusting the power supply to the heater 207 based on temperature information detected by the temperature sensor 263, the temperature distribution inside the processing chamber 201 becomes desired. The temperature sensor 263 is installed along the inner wall of the reaction tube 203, similar to the nozzles 249a and 249b.

[0035] (Control device) Next, the control device will be described with reference to Fig. 4. As shown in Fig. 4, controller 121, which is a control unit (control device), is configured as a computer including a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, storage device 121c, and I / O port 121d. RAM 121b, storage device 121c, and I / O port 121d are configured to be able to exchange data with CPU 121a via internal bus 121e. An input / output device 122 configured as, for example, a touch panel, is connected to controller 121.

[0036] The storage device 121c is configured with, for example, a flash memory, an HDD (Hard Disk Drive), an SSD (Solid State Drive), etc. Control programs for controlling the operation of the substrate processing apparatus, process recipes describing procedures and conditions for film formation processes (described later), etc., are readably recorded and stored in the storage device 121c. A process recipe is a combination of procedures for various processes (film formation processes) (described later) that are executed by the controller 121 in the substrate processing apparatus to obtain a predetermined result, and functions as a program. Hereinafter, process recipes, control programs, etc. are collectively referred to simply as programs. A process recipe is also simply referred to as a recipe. In this specification, the term "program" may refer to a recipe alone, a control program alone, or both. The RAM 121b is configured as a memory area (work area) for temporarily storing programs, data, etc. read by the CPU 121a.

[0037] The I / O port 121d is connected to the above-mentioned MFCs 241a to 241g, valves 243a to 243g, pressure sensor 245, APC valve 244, vacuum pump 246, heater 207, temperature sensor 263, rotation mechanism 267, boat elevator 115, shutter opening / closing mechanism 115s, RF power supply 320, etc.

[0038] The CPU 121a is configured to read and execute a control program from the storage device 121c, and to read a recipe from the storage device 121c in response to an input of an operation command from the input / output device 122. The CPU 121a is configured to be able to control, in accordance with the contents of the read recipe, the control of the rotation mechanism 267, the flow rate adjustment operation of various gases by the MFCs 241a to 241g, the opening and closing operation of the valves 243a to 243g, the opening and closing operation of the APC valve 244 and the pressure adjustment operation by the APC valve 244 based on the pressure sensor 245, the start and stop of the vacuum pump 246, the temperature adjustment operation of the heater 207 based on the temperature sensor 263, the forward / reverse rotation of the boat 217 by the rotation mechanism 267, the adjustment of the rotation angle and rotation speed, the raising and lowering operation of the boat 217 by the boat elevator 115, the opening and closing operation of the shutter 219s by the shutter opening / closing mechanism 115s, the power supply of the RF power source 320, and the like.

[0039] The controller 121 can be configured by installing the above-mentioned program recorded and stored in the external storage device 123 into a computer. The storage device 121c and the external storage device 123 are configured as computer-readable recording media. Hereinafter, these will be collectively referred to simply as recording media. When the term recording media is used in this specification, it may include only the storage device 121c alone, only the external storage device 123 alone, or both. Note that the program may be provided to the computer using a communication means such as the Internet or a dedicated line, without using the external storage device 123.

[0040] (2) Substrate processing process An example of a process sequence for forming a film on a wafer 200 as a substrate, i.e., a film formation sequence, using the above-described substrate processing apparatus as one step in the manufacturing process of a semiconductor device will be described. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by a controller 121.

[0041] In the film formation sequence of this embodiment, (a) Step A of supplying a first gas containing a first element and a halogen element to the wafer 200; (b) Step B of supplying a second gas containing a second element different from the first element and hydrogen (H) to the wafer 200; (c) Step C of supplying a H-containing gas different from the plasma-excited second gas to the wafer 200; (d) Step D of supplying a third gas containing a third element different from the first element and the second element to the wafer 200; The process includes performing a cycle in which step C is performed after step A and step B and before step D a predetermined number of times (n times, where n is an integer of 1 or 2 or more), thereby forming a film containing the first element, the second element, and the third element on the wafer 200.

[0042] In this specification, the above-described processing sequence may be expressed as follows for convenience: Similar notations will be used in the following descriptions of other aspects and modifications.

[0043] (First gas → purge → second gas → purge → plasma-excited H-containing gas → purge → third gas → purge) × n

[0044] In addition, in the processing sequence shown in Figure 5, In step A, a first gas is supplied through the nozzle 249a (R1); In step B, a second gas is supplied through the nozzle 249b (R2); In step C, H-containing gas is supplied through the nozzles 249a and 249b (R1 and R2), In step D, an example is shown in which the third gas is supplied through the nozzle 249b (R2).

[0045] In Figure 5, In step C, an example is shown in which the supply of the H-containing gas to the wafer 200 is started before the plasma excitation of the H-containing gas is started. These processing sequences can be expressed as follows:

[0046] {(R1: first gas) → purge → (R2: second gas) → purge → [(R1, R2: H-containing gas) → (R1, R2: plasma-excited H-containing gas)] → purge → (R2: third gas) → purge} × n

[0047] The term "wafer" used in this specification may refer to the wafer itself or a laminate of the wafer and a predetermined layer or film formed on its surface. The term "surface of a wafer" used in this specification may refer to the surface of the wafer itself or the surface of a predetermined layer or the like formed on the wafer. When described in this specification, "forming a predetermined layer on a wafer" may mean forming a predetermined layer directly on the surface of the wafer itself or forming a predetermined layer on a layer or the like formed on the wafer. When used in this specification, the term "substrate" is synonymous with the term "wafer".

[0048] The term "layer" as used herein includes at least one of a continuous layer and a discontinuous layer. For example, the first to third layers described below may include a continuous layer, a discontinuous layer, or both.

[0049] In this specification, for example, when it is stated that the first to third gases are adsorbed to or react with the surface of the wafer 200, it may include not only the case where they are adsorbed to or react with the wafer surface without being decomposed, but also the case where they are decomposed or an intermediate formed by the detachment of their ligands is adsorbed to or reacts with the surface of the wafer 200.

[0050] (Wafer charge) A plurality of wafers 200 are loaded into the boat 217. Thereafter, the shutter 219s is moved by the shutter opening / closing mechanism 115s to open the lower end opening of the manifold 209. The wafers 200 include product wafers and dummy wafers.

[0051] (boat load) 1, the boat 217 supporting the plurality of wafers 200 is lifted by the boat elevator 115 and loaded into the processing chamber 201. In this state, the seal cap 219 seals the lower end of the manifold 209.

[0052] (pressure and temperature regulation) After the boat loading is completed, the processing chamber 201, i.e., the space in which the wafers 200 are present, is evacuated (reduced pressure exhausted) by the vacuum pump 246 so that the interior of the processing chamber 201 is at a desired pressure (vacuum level). At this time, the pressure inside the processing chamber 201 is measured by the pressure sensor 245, and the APC valve 244 is feedback-controlled based on the measured pressure information (pressure adjustment). Furthermore, the wafers 200 inside the processing chamber 201 are heated by the heater 207 so that the processing temperature is at a desired processing temperature. At this time, the power supply to the heater 207 is feedback-controlled based on temperature information detected by the temperature sensor 263 so that the processing chamber 201 has a desired temperature distribution (temperature adjustment). Furthermore, the rotation mechanism 267 starts to rotate the wafers 200. The evacuation inside the processing chamber 201 and the heating and rotation of the wafers 200 are all continued at least until the processing of the wafers 200 is completed.

[0053] (film formation process) Then, the following steps A, B, C, and D are executed in sequence.

[0054] [Step A] In step A, a first gas containing a first element and a halogen element is supplied to the wafer 200 in the processing chamber 201 .

[0055] Specifically, the valve 243a is opened to allow a first gas to flow into the gas supply pipe 232a. The flow rate of the first gas is adjusted by the MFC 241a, supplied into the processing chamber 201 through the nozzle 249a, and exhausted from the exhaust port 231a. At this time, the first gas is supplied to the wafer 200 (first gas supply). At this time, the valves 243f and 243g may be opened to supply an inert gas into the processing chamber 201 through each of the nozzles 249a and 249b. In this step, the inert gas supplied through the nozzle 249a acts, for example, as a carrier gas and / or a dilution gas for the first gas. The inert gas supplied through the nozzle 249b is supplied to prevent gas from entering the nozzle 249b (backflow) and may also be supplied for other purposes, such as adjusting the gas flow in the processing chamber 201.

[0056] The processing conditions in this step are as follows: Treatment temperature: 150 to 800°C, preferably 180 to 700°C, more preferably 400 to 700°C Treatment pressure: 1 to 2666 Pa, preferably 67 to 1333 Pa First gas supply flow rate: 0.001 to 2 slm, preferably 0.01 to 1 slm First gas supply time: 1 to 120 seconds, preferably 1 to 60 seconds Inert gas supply flow rate (per gas supply pipe): 0 to 10 slm is exemplified.

[0057] In this specification, when a numerical range such as "150 to 800°C" is expressed, both the lower and upper limits are included in the range. For example, "150 to 800°C" means "150°C or higher and 800°C or lower." The same applies to other numerical ranges. In this specification, the process temperature refers to the temperature of the wafer 200 or the temperature inside the process chamber 201, and the process pressure refers to the pressure inside the process chamber 201, in other words, the pressure in the space in which the wafer 200 is present. The process time refers to the time the process continues. The pipe temperature refers to the temperature inside the pipe. When the supply flow rate includes 0 slm, 0 slm means that the substance (gas) is not supplied. These terms also apply to the following description.

[0058] By supplying a first gas (source gas) containing a first element and a halogen element to the wafer 200 under the above-described conditions, a first layer is formed on the top surface of the wafer 200, which serves as a base. For example, when a chlorosilane-based gas containing silicon (Si) as the first element and chlorine (Cl) as the halogen element is used as the first gas, a Si-containing layer containing Cl is formed as the first layer on the top surface of the wafer 200. The first layer may be an adsorption layer (a physisorption layer or a chemisorption layer) formed by decomposition of the first gas or a portion of the first gas, or may be a deposition layer of Si containing Cl.

[0059] In this embodiment, as an example, a case will be described in which a H-containing chlorosilane gas containing Si as a first element, Cl as a halogen element, and H is used as the first gas.

[0060] By supplying the first gas to the wafer 200 under the above conditions, Si—H bonds, Si—Cl bonds, etc. are formed in the first layer.

[0061] After the first layer is formed, the valve 243a is closed to stop the supply of the first gas into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove any remaining gases from the processing chamber 201. At this time, the valves 243f and 243g are opened to supply an inert gas into the processing chamber 201, thereby purging the processing chamber 201 with the inert gas. Note that at this time, the supply of the first gas and a second gas, which will be described later, into the processing chamber 201 is not performed. In this embodiment, the process of not supplying the first gas and the second gas and evacuating the processing chamber 201 may be referred to as step F.

[0062] The first gas may be, for example, a halosilane-based gas containing, in one molecule, Si as the first element, which is the main element constituting the film formed on the wafer 200, and a halogen element. Halogen elements include Cl, fluorine (F), bromine (Br), iodine (I), etc. The halosilane-based gas may be, for example, the above-mentioned chlorosilane-based gas containing Si and Cl.

[0063] The first gas may be, for example, a H-containing chlorosilane gas such as monochlorosilane (SiH3Cl) gas, dichlorosilane (SiH2Cl2) gas, trichlorosilane (SiHCl3) gas, etc. One or more of these may be used as the first gas.

[0064] As the first gas, in addition to a chlorosilane-based gas, for example, a H-containing fluorosilane-based gas such as difluorosilane (SiH2F2) gas or trifluorosilane (SiHF3), a H-containing bromosilane-based gas such as dibromosilane (SiH2Br2) gas or tribromosilane (SiHBr3), or a H-containing iodosilane-based gas such as diiodosilane (SiH2I2) gas or triiodosilane (SiHI3) gas can be used. One or more of these can be used as the first gas.

[0065] The first gas may be, for example, a non-H-containing halosilane gas such as tetrachlorosilane (SiCl4) gas, hexachlorodisilane (Si2Cl6) gas, octachlorotrisilane (Si3Cl8) gas, tetrafluorosilane (SiF4) gas, hexafluorodisilane (Si2F6) gas, tetrabromosilane (SiBr4) gas, hexabromodisilane (Si2Br6) gas, tetraiodosilane (SiI4) gas, or hexaiododisilane (Si2I6) gas. One or more of these may be used as the first gas. However, it is more preferable to use the above-mentioned H-containing halosilane gas as the first gas.

[0066] The inert gas may be, for example, nitrogen (N2) gas or a rare gas such as argon (Ar) gas, helium (He) gas, neon (Ne) gas, or xenon (Xe) gas. One or more of these may be used as the inert gas. This also applies to each step described below.

[0067] [Step B] After step A is completed, a second gas containing a second element different from the first element and H in one molecule is supplied to the wafer 200 in the processing chamber 201, that is, to the first layer formed on the wafer 200.

[0068] Specifically, the valve 243b is opened to allow the second gas to flow into the gas supply pipe 232b. The flow rate of the second gas is adjusted by the MFC 241b, and the second gas is supplied into the processing chamber 201 through the nozzle 249b and exhausted from the exhaust port 231a. At this time, the second gas is supplied to the wafer 200 (second gas supply). At this time, the valves 243f and 243g may be opened to supply an inert gas into the processing chamber 201 through each of the nozzles 249a and 249b. In this step, the inert gas supplied through the nozzle 249b acts, for example, as a carrier gas and / or a dilution gas for the second gas. The inert gas supplied through the nozzle 249a is supplied, for example, to prevent gas from entering the nozzle 249a (backflow).

[0069] The processing conditions in this step are as follows: Treatment temperature: 150 to 800°C, preferably 180 to 700°C, more preferably 400 to 700°C Treatment pressure: 1 to 4000 Pa, preferably 10 to 1000 Pa Second gas supply flow rate: 0.1 to 20 slm, preferably 1 to 10 slm Second gas supply time: 1 to 120 seconds, preferably 10 to 60 seconds Inert gas supply flow rate (per gas supply pipe): 0 to 10 slm is exemplified.

[0070] By supplying the wafer 200 with a second gas (reactive gas) containing a second element and H in one molecule under the above conditions, at least a portion of the first layer formed on the wafer 200 is modified to form a second layer. When, for example, a hydrocarbon gas (carbonizing agent) containing carbon (C) and H as the second element is used as the second gas, at least a portion of the first layer formed on the wafer 200 is carbonized to form a second layer. As a result, for example, a silicon carbide layer (SiC layer) containing Si as the first element and C as the second element is formed on the outermost surface of the wafer 200 as the second layer.

[0071] In this embodiment, as an example, a case will be described in which a hydrocarbon-based gas containing C and H as the second element is used as the second gas.

[0072] By supplying the second gas to the wafer 200 under the above-mentioned conditions, new bonds such as C—H bonds, C—C bonds, and Si—C bonds are formed in the second layer in addition to the Si—H bonds and Si—Cl bonds contained in the first layer described above.

[0073] After the second layer is formed, the valve 243b is closed to stop the supply of the second gas into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove gases remaining in the processing chamber 201. At this time, the valves 243f and 243g are opened to supply an inert gas into the processing chamber 201, and the processing chamber 201 is purged with the inert gas.

[0074] As the second gas, for example, a hydrocarbon-based gas containing C and H as second elements can be used. As the hydrocarbon-based gas, for example, ethylene (C2H4) gas, propylene (C3H6) gas, butene (C4H8) gas, etc. can be used. Of these, it is more preferable to use C3H6 gas or C4H8 gas containing a methyl group as the second gas.

[0075] [Step C] After step B is completed, an H-containing gas different from the second gas is excited into a plasma state and supplied to the wafers 200 in the processing chamber 201, i.e., the second layer formed on the wafers 200. In this embodiment, step C includes a period in which the H-containing gas is supplied without being excited into a plasma state before the H-containing gas is excited into a plasma state and supplied to the wafers 200. In other words, in step C, step C1 is performed in which the H-containing gas is supplied without being excited into a plasma state, and after a predetermined period has elapsed, step C2 is performed in which the H-containing gas in the processing chamber 201 is excited into a plasma state while the supply of the H-containing gas is continued. Steps C1 and C2 will be described below.

[0076] (1) Step C1 After step B is completed, a H-containing gas different from the second gas is supplied to the wafer 200 in the processing chamber 201, that is, to the second layer formed on the wafer 200.

[0077] Specifically, the valve 243d is opened to allow the H-containing gas to flow into the gas supply pipe 232b. The H-containing gas has a flow rate adjusted by the MFC 241b, is supplied into the processing chamber 201 through the nozzle 249b, and is exhausted from the exhaust port 231a. At this time, the H-containing gas is supplied to the wafer 200 (H-containing gas supply). At this time, the valve 243c is opened to supply the H-containing gas to the nozzle 249a. In this step, the H-containing gas is supplied through the nozzle 249a to prevent, for example, the intrusion (backflow) of gas into the nozzle 249a. At this time, the valves 243f and 243g are closed to stop the supply of the inert gas into the processing chamber 201. That is, in this step, in order to prevent backflow, etc., only the H-containing gas is supplied to the nozzle 249a, and no gas other than the H-containing gas is supplied to the nozzle 249a. An inert gas, such as a carrier gas for the H-containing gas, is also not supplied to the nozzle 249b. In particular, N2 gas used as an inert gas is not supplied to the nozzles 249a and 249b.

[0078] The processing conditions in this step are as follows: Treatment temperature: 150 to 800°C, preferably 180 to 700°C, more preferably 400 to 700°C Treatment pressure: 2 to 100 Pa, preferably 20 to 70 Pa H-containing gas supply flow rate (R2): 0.05~20slm H-containing gas supply flow rate (R1): 0.0001 to 0.003 slm H-containing gas supply time (for each R1 and R2): 1 to 100 seconds, preferably 1 to 30 seconds is exemplified.

[0079] By supplying the H-containing gas to the wafer 200 under the above-described conditions, specifically by supplying the H-containing gas to the wafer 200 via the nozzle 249b, gases other than the H-containing gas, such as N2 gas and the second gas (i.e., residual gas), remaining in the processing chamber 201 can be purged with the H-containing gas. This step may be performed until at least a portion of the residual gas in the processing chamber 201 is exhausted, and the supply time of the H-containing gas is preferably shorter than the supply time of the H-containing gas in step C2. Furthermore, in this step, the exhaust speed in the processing chamber 201 can be increased compared to step C2 by adjusting the APC valve 244.

[0080] (2) Step C2 When a predetermined period of time has elapsed since the start of step C1, the H-containing gas supplied into the processing chamber 201 is excited into a plasma state while the supply of the H-containing gas is continued.

[0081] Specifically, while the supply of the H-containing gas into the processing chamber 201 via the nozzles 249a and 249b continues, RF power is applied from the RF power supply 320 to the electrode 300. As a result, the H-containing gas supplied into the processing chamber 201 is excited into a plasma state inside the processing chamber 201, and the H * and H2 * and the like are generated and supplied to the second layer formed on the wafer 200 (plasma excited H-containing gas supply). * and H2 * Thus, an H-containing gas containing activated species such as H is supplied. Note that * denotes radicals. The same applies to the following explanation. At this time, the valves 243f and 243g are kept closed. That is, in this step as well, as in step C1, only the H-containing gas is supplied into the processing chamber 201 through the nozzles 249a and 249b, and no gas other than the H-containing gas is supplied into the processing chamber 201. In particular, as in step C1, N2 gas used as an inert gas is not supplied to the nozzles 249a and 249b.

[0082] The processing conditions in this step are as follows: Treatment temperature: 150 to 800°C, preferably 180 to 700°C, more preferably 400 to 700°C Treatment pressure: 2 to 100 Pa, preferably 20 to 70 Pa H-containing gas supply flow rate (R2): 0.1 to 10 slm H-containing gas supply flow rate (R1): 0.005 to 0.03 slm H-containing gas supply time (for each R1 and R2): 10 to 600 seconds, preferably 1 to 50 seconds RF power: 100~1000W RF frequency: 25MHz~35MHz is exemplified.

[0083] By supplying the H-containing gas to the wafer 200 under the above conditions after exciting it into a plasma state, impurities such as Cl and H contained in the second layer (SiC layer) formed on the wafer 200 are converted into H * and H2 * etc., and can be removed from the second layer.

[0084] Under the above conditions, the H-containing gas is excited into a plasma state and supplied to the wafer 200, thereby breaking the Si-H bonds and Si-Cl bonds in the second layer. The H and Cl atoms that have been cut from their bonds with Si are desorbed from the second layer, thereby forming dangling bonds of Si in the second layer.

[0085] Furthermore, by supplying the H-containing gas excited to a plasma state to the wafer 200 under the above conditions, the C-H bonds in the second layer are broken. The H that has been cut from its bond with C is desorbed from the second layer, thereby forming dangling C bonds in the second layer.

[0086] After removing the impurities contained in the second layer, the valves 243c and 243d are closed to stop the supply of the H-containing gas into the processing chamber 201. Furthermore, the supply of RF power to the electrode 300 is stopped. Then, the processing chamber 201 is evacuated to remove gases remaining in the processing chamber 201. At this time, the supply of the H-containing gas and a third gas (described later) into the processing chamber 201 is not performed. In this embodiment, the process of evacuating the processing chamber 201 without supplying the H-containing gas and the third gas is sometimes referred to as step E. In step E, it is preferable to remove gases remaining in the processing chamber 201 only by evacuating the processing chamber 201 without performing a step of purging the processing chamber 201, or to supply an inert gas other than N2 gas as a purge gas when purging the processing chamber 201. Here, "purging" refers to the removal of H2 remaining in the processing chamber 201 by supplying an inert gas into the processing chamber 201. * "Vacuum evacuation" refers to the removal of activated species such as H2 and other by-products from the processing chamber 201 without supplying an inert gas for purging the processing chamber 201. * This means removing active species such as nitrite and nitrite.

[0087] The H-containing gas used in steps C1 and C2 may be, for example, H gas as a simple hydrogen gas or a mixed gas containing H gas and a rare gas such as Ar gas or He gas. All H-containing gases do not contain nitrogen (N). One or more of these may be used as the H-containing gas. That is, in step C2, plasma-excited H gas or the plasma-excited mixed gas is supplied to the wafer 200, and plasma-excited N-containing gas is not supplied to the wafer 200. The H-containing gas used in step C1 and the H-containing gas used in step C2 may be the same gas or may be different H-containing gases.

[0088] [Step D] After step C is completed, a third gas containing a third element different from the first element and the second element is supplied to the wafer 200 in the processing chamber 201, that is, to the second layer formed on the wafer 200.

[0089] Specifically, the valve 243e is opened to allow the third gas to flow into the gas supply pipe 232e. The flow rate of the third gas is adjusted by the MFC 241e, and the third gas is supplied into the processing chamber 201 through the nozzle 249b and exhausted from the exhaust port 231a. At this time, the third gas is supplied to the wafer 200 (third gas supply). At this time, the valves 243f and 243g may be opened to supply an inert gas into the processing chamber 201 through the nozzles 249a and 249b, respectively.

[0090] The processing conditions in this step are as follows: Treatment temperature: 150 to 800°C, preferably 180 to 700°C, more preferably 400 to 700°C Treatment pressure: 1 to 4000 Pa, preferably 10 to 1000 Pa Third gas supply flow rate: 0.1 to 20 slm, preferably 1 to 10 slm Third gas supply time: 1 to 120 seconds, preferably 10 to 60 seconds Inert gas supply flow rate (per gas supply pipe): 0 to 10 slm is exemplified.

[0091] In this step, the third gas is supplied to the wafer 200 in a non-plasma atmosphere (that is, under conditions where plasma is not excited).

[0092] By supplying a third gas (reactive gas) containing a third element to the wafer 200 under the above-described conditions, at least a portion of the second layer formed on the wafer 200 is modified to form a third layer. When, for example, a nitriding gas (nitriding agent) containing N as the third element is used as the third gas, at least a portion of the second layer formed on the wafer 200 is nitrided to form a third layer. As a result, for example, a silicon carbonitride layer (SiCN layer) containing Si as a first element, C as a second element, and N as a third element is formed on the outermost surface of the wafer 200 as the third layer.

[0093] In this embodiment, as an example, a case where a hydrogen nitride gas containing N and H as third elements is used as the third gas will be described.

[0094] By supplying the third gas to the wafer 200 under the above conditions, Si-N bonds in which dangling bonds of Si are bonded to N, C-N bonds in which dangling bonds of C are bonded to N, etc. are formed in the third layer.

[0095] After the third layer is formed, the valve 243e is closed to stop the supply of the third gas into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove gases remaining in the processing chamber 201. At this time, the valves 243f and 243g are opened to supply an inert gas into the processing chamber 201, and the processing chamber 201 is purged with the inert gas.

[0096] The third gas may be, for example, a hydrogen nitride gas containing N and H as third elements. The hydrogen nitride gas may be, for example, ammonia (NH) gas, diazene (NH) gas, hydrazine (NH) gas, NH gas, etc. The third gas may be one or more of these.

[0097] [Perform the cycle a specified number of times] By performing the above-described steps A, B, C, and D asynchronously, i.e., by performing a cycle a predetermined number of times (n times, where n is an integer of 1 or 2 or more), a film of a predetermined thickness can be formed on the surface of the wafer 200. For example, when Si is used as the first element, C is used as the second element, and N is used as the third element, as described above, a silicon carbonitride film (SiCN film) of a predetermined thickness can be formed on the surface of the wafer 200. It is preferable to repeat the above-described cycle multiple times. That is, it is preferable to make the thickness of the SiCN layer formed per cycle thinner than the desired film thickness, and to repeat the above-described cycle multiple times until the thickness of the SiCN film formed by stacking the SiCN layers reaches the desired thickness.

[0098] (After purging and atmospheric pressure recovery) After the process of forming a SiCN film of a desired thickness on the wafer 200 is completed, an inert gas is supplied as a purge gas from each of the nozzles 249a and 249b into the processing chamber 201 and exhausted from the exhaust port 231a. This purges the processing chamber 201, and gases and reaction by-products remaining in the processing chamber 201 are removed from the processing chamber 201. Thereafter, the atmosphere in the processing chamber 201 is replaced with the inert gas (inert gas replacement), and the pressure in the processing chamber 201 is returned to normal pressure.

[0099] (Boat unloading) Thereafter, the seal cap 219 is lowered by the boat elevator 115, and the lower end of the manifold 209 is opened. Then, the processed wafers 200, supported by the boat 217, are carried out from the lower end of the manifold 209 to the outside of the reaction tube 203 (boat unloading). After the boat unloading, the shutter 219s is moved, and the lower end opening of the manifold 209 is sealed by the shutter 219s via the O-ring 220c. The processed wafers 200 are removed from the boat 217.

[0100] This completes the series of processes for forming a film on the wafer 200. This series of processes is performed a predetermined number of times (one or more times).

[0101] (3) Effects of this mode According to this aspect, one or more of the following effects can be obtained.

[0102] (a) By performing step C after steps A and B, impurities such as H and Cl derived from the first gas (H-containing chlorosilane gas) and H derived from the second gas (hydrocarbon gas) can be removed from the second layer (SiC layer). In this way, impurities can be effectively removed from the SiCN film. This can improve the film density of the SiCN film and enhance its ashing resistance.

[0103] By performing step C after steps A and B, step C can cleave Si-H bonds, Si-Cl bonds, etc. derived from the first gas, and C-H bonds, etc. derived from the second gas. In particular, by removing not only H and Cl, etc., bonded to Si, but also H bonded to C from the second layer, dangling bonds highly reactive with Si and C can be formed in the second layer. In this way, increasing the number of dangling bonds in the second layer can enhance reactivity with the third gas supplied in step D and with the first and second gases supplied in steps A and B of the next cycle. As a result, an improvement in film formation rate can be achieved.

[0104] Furthermore, by performing step C after steps A and B, step C can cleave Si-H bonds, Si-Cl bonds, and the like derived from the first gas, and C-H bonds and the like derived from the second gas. When dangling Si and C bonds are formed in this way, they may bond to form stable bonds in the second layer, such as Si-C-Si bonds, in which the number of Si bonds to C is large (see FIGS. 6(a) and 6(b)). Furthermore, by continuing to perform step C, it may be possible to increase more stable Si-C-Si bonds and the like (see FIG. 6(c)). This can suppress desorption of C from the second layer, even if a plasma-excited H-containing gas is supplied to the second layer formed on the wafer 200 in step C of the next cycle, for example. This can maintain the C composition ratio in the SiCN film. Furthermore, as described above, in step C, the number of dangling bonds of Si and C in the second layer is increased, which makes it easier for C derived from the second gas supplied in step B of the next cycle to bond to Si and C in the second layer. As a result, the composition ratio of C in the SiCN film can be improved.

[0105] By performing step C before step D, it is possible to suppress a decrease in the composition ratio of C in the SiCN film. This will be described below. If step C is performed after step D, the third gas (hydrogen nitride gas) is supplied in step D before the plasma-excited H-containing gas is supplied in step C, and relatively strong Si-N bonds originating from the third gas are formed on the wafer 200. Therefore, even if C-H bonds originating from the second gas are broken by supplying the plasma-excited H-containing gas in step C, new Si-C bonds are unlikely to be formed, and C is likely to be desorbed from the second layer (SiC layer). In this state, step C is continued, and H2 * When the cleavage of C bonds (C—C bonds, Si—C bonds, etc.) progresses due to the above, C is desorbed from the second layer, which may result in a decrease in the composition ratio of C in the SiCN film.

[0106] Therefore, even if the number of dangling bonds of Si and C is increased in step C to make it easier for C derived from the second gas supplied in step B of the next cycle to bond to Si and C in the second layer, the effect of maintaining or improving the composition ratio of C in the SiCN film is limited. Note that, in step C, when C is desorbed from the second layer, the number of adsorption sites terminated by NH groups derived from the third gas on the wafer 200 increases, and as a result, the composition ratio of N in the SiCN film tends to increase.

[0107] In the present disclosure, by performing step C before step D, highly stable bonds such as Si-C-Si bonds can be formed in the second layer before strong Si-N bonds are formed, thereby suppressing a decrease in the C composition ratio in the SiCN film.

[0108] (b) In step D, the third gas is supplied to the wafer 200 in a non-plasma manner (i.e., under conditions where plasma excitation is not performed), thereby suppressing desorption of C from the second layer, and thus maintaining or improving the composition ratio of C in the SiCN film.

[0109] (c) In step C, the H-containing gas supplied to the wafer 200 is a gas that does not contain N, so that impurities such as Cl and H can be desorbed while suppressing desorption of C and the like from the second layer, compared to when a gas containing N is used. This allows highly stable bonds such as Si-C-Si bonds to be formed in the second layer, thereby improving the composition ratio of C in the SiCN film.

[0110] (d) In step C, an H-containing gas is supplied to the wafer 200 through the nozzle 249b (R2), and an H-containing gas is supplied to the nozzle 249a (R1). That is, in step C, only an H-containing gas is supplied into the processing chamber 201 through the nozzles 249a and 249b, and no gas other than the H-containing gas is supplied into the processing chamber 201. In particular, in step C, N2 gas used as an inert gas is not supplied to the nozzles 249a and 249b. This can suppress a decrease in the composition ratio of C in the SiCN film.

[0111] If, for example, an N-containing gas such as N gas is supplied to the nozzle 249a as a backflow prevention gas in step C, the N-containing gas is plasma-excited together with the H-containing gas supplied through the nozzle 249b and supplied to the wafer 200. At this time, activated species generated by the plasma excitation of the N-containing gas are supplied to the wafer 200, causing excessive desorption of C from the second layer. This reduces the composition ratio of C in the SiCN film. In the present disclosure, as described above, in step C, the gas supplied to the nozzle 249a as a backflow prevention gas or the like is an H-containing gas, thereby making it possible to prevent excessive desorption of C from the second layer.

[0112] (e) In step C, by performing step C1 of supplying an H-containing gas into the processing chamber 201 before starting step C2 of plasma-exciting the H-containing gas, gases other than the H-containing gas (particularly N-containing gases such as N gas) remaining in the processing chamber 201 can be purged with the H-containing gas. This reduces the influence of other gases that are plasma-excited (directly excited or indirectly excited by the plasma-excited H-containing gas) together with the H-containing gas on the substrate processing in step C2. In particular, even if the processing chamber 201 is purged with N gas before step C, the N gas in the processing chamber 201 is purged with the H-containing gas before starting step C2. This prevents the remaining N gas from being plasma-excited and desorbing C from the second layer in step C2.

[0113] (f) By using H-containing chlorosilane gas as the first gas supplied to the wafer 200 in step A, it is possible to form H termination in addition to Cl termination (halogen termination) on the surface of the wafer 200 after step A. This increases the probability of adsorption of the second gas (hydrocarbon gas) which is less likely to be adsorbed to the halogen termination.

[0114] (g) In step F, by not supplying the first gas and the second gas, the gas phase reaction between the first gas and the second gas in step F is suppressed, and as a result, the step coverage and composition controllability of the SiCN film can be improved.

[0115] (h) In step E, the supply of the H-containing gas and the third gas is not performed, so that the third gas (hydrogen nitride gas) is not supplied to the H2 * etc., which can suppress the desorption of C in the second layer. Furthermore, in step E, by supplying an inert gas other than N gas into the processing chamber 201 as a purge gas, it is possible to suppress the desorption of C in the second layer.

[0116] (i) In step C, H and Cl bonded to Si can be desorbed from the second layer (SiC layer) to form dangling Si bonds, which can promote adsorption of the third gas supplied in step D, and particularly the first and second gases supplied in steps A and B of the next cycle, to the dangling Si bonds.

[0117] (j) In step C, H bonded to C can be desorbed from the second layer (SiC layer) to form dangling bonds of C. This can promote adsorption of the third gas supplied in step D and the first and second gases supplied in steps A and B of the next cycle to the dangling bonds of C.

[0118] (k) By performing a cycle including step C, the composition ratio of C in the SiCN film can be made larger than the composition ratio of C in the SiCN film formed by performing a cycle including steps A, B, and D but not including step C.

[0119] (l) By performing a cycle in which step C is performed before step D, the composition ratio of C in the SiCN film can be made larger than that of an SiCN film formed by performing a cycle that includes steps A to D and in which step C is performed after step D.

[0120] <Other Aspects of the Present Disclosure> Although the embodiments of the present disclosure have been specifically described above, the present disclosure is not limited to the above embodiments and can be modified in various ways without departing from the spirit and scope of the present disclosure.

[0121] In the above-described embodiment, the first element is Si, a metalloid element, but the present disclosure is not limited thereto. For example, the present disclosure can be applied to cases where other metalloid elements such as boron (B), germanium (Ge), arsenic (As), antimony (Sb), and tellurium (Te) are used as the first element. The present disclosure can also be applied to cases where metal elements such as aluminum (Al), titanium (Ti), hafnium (Hf), zirconium (Zr), tantalum (Ta), molybdenum (Mo), and tungsten (W) are used as the first element. Furthermore, the first gas can be, for example, a halosilane-based gas containing the above-described other metalloid element or the above-described metal element as the first element and also containing a halogen element. This embodiment also provides the same effects as the above-described embodiment.

[0122] Although not specifically described in the above embodiment, the first gas is preferably a gas that does not contain the second element. This embodiment also provides the same effects as the above embodiment. Furthermore, this embodiment also makes it possible to easily control, for example, the composition ratio of the second element in the film formed on wafer 200 by adjusting the supply conditions of the second gas in step B.

[0123] In the above-described embodiment, C is used as an example of the second element, and a hydrocarbon-based gas is used as an example of the second gas containing the second element and H. However, the present disclosure is not limited thereto. For example, B may be used as the second element, and a boron-based gas such as monoborane (BH) gas or diborane (BH) gas may be used as the second gas containing the second element and H. Alternatively, for example, B and C may be used as the second element, and both these boron-based gases and the above-described hydrocarbon-based gases may be used as the second gas containing the second element and H. In this embodiment, the same effects as those in the above-described embodiment can be obtained.

[0124] In the above-described embodiment, a nitriding gas (nitriding agent) containing N as a third element is used as the third gas. However, the present disclosure is not limited thereto. For example, the present disclosure can be applied to a case where a silicon oxycarbide film (SiOC film, i.e., a C-containing silicon oxide film) containing Si as a first element, C as a second element, and O as a third element is formed on the wafer 200 by using an oxidizing gas (oxidizing agent) containing oxygen (O) as the third element. Examples of the O-containing third gas include oxygen (O) gas, ozone (O) gas, water vapor (H0 gas), hydrogen peroxide (H0) gas, and a mixed gas of O and H. One or more of these gases can be used as the O-containing third gas. This embodiment also achieves at least some of the effects of the above-described embodiments.

[0125] In the above embodiment, an example in which the third gas is supplied to the wafer 200 in a non-plasma atmosphere in step D has been described, but the present disclosure is not limited to this. For example, the third gas can be supplied to the wafer 200 in a plasma atmosphere (i.e., under conditions that cause plasma excitation). Even in this case, it is desirable to supply the plasma-excited third gas under conditions that can suppress desorption of C from the second layer.

[0126] It is preferable that the recipes used for each process are individually prepared according to the process contents, and are recorded and stored in the storage device 121c via an electric communication line or the external storage device 123. Then, when starting each process, it is preferable that the CPU 121a appropriately selects an appropriate recipe according to the process contents from the multiple recipes recorded and stored in the storage device 121c.

[0127] The above-mentioned recipes do not necessarily have to be newly created, but may be prepared by modifying an existing recipe already installed in the substrate processing apparatus, for example. When modifying a recipe, the modified recipe may be installed in the substrate processing apparatus via an electric communication line or a recording medium on which the modified recipe is recorded. Alternatively, an existing recipe already installed in the substrate processing apparatus may be directly modified by operating the input / output device 122 provided in the existing substrate processing apparatus.

[0128] The present disclosure is not limited to the above-described embodiment and can be suitably applied, for example, to a case where a film is formed using a single-wafer substrate processing apparatus that processes one or several substrates at a time. The present disclosure is also not limited to the above-described embodiment and can be suitably applied to a case where a film is formed using a substrate processing apparatus having a cold-wall processing furnace. In the above-described embodiment, an example in which the first to third gases are activated by heat has been described. However, the present disclosure is not limited thereto. For example, the present disclosure can also be suitably applied to a case in which the gas is activated by plasma generated inside or outside the processing chamber 201, or a case in which the gas is activated by irradiating the gas with electromagnetic waves using a lamp or the like.

[0129] When using these substrate processing apparatuses, each process can be performed using the same processing procedures and conditions as in the above-described embodiments and modifications, and the same effects as in the above-described embodiments and modifications can be obtained.

[0130] The above-described embodiments and modifications may be used in combination as appropriate. The processing procedures and processing conditions in such a case may be the same as those of the above-described embodiments and modifications, for example. [Example]

[0131] For Samples 1 to 3, a SiCN film was formed on a wafer using the substrate processing apparatus shown in FIG.

[0132] Sample 1 was produced by repeating a cycle of steps A, B, and D in this order n times, without performing step C. Sample 2 was produced by repeating a cycle of steps A, B, D, and C in this order n times. Sample 3 was produced by repeating a cycle of steps A, B, C, and D in this order n times. The processing conditions for each step in producing Samples 1 to 3 were set to predetermined processing conditions within the processing condition range for each step in the above-mentioned embodiment.

[0133] The thickness of the SiCN film of each sample was then measured, and the thickness of the SiCN film formed per cycle (Å / cycle) was calculated. The composition ratio (atomic %) of the SiCN film of each sample, i.e., the concentration of Si, N, and C contained in the SiCN film of each sample, was also measured using XPS (X-ray photoelectron spectroscopy). These results are shown in Figure 7.

[0134] As shown in Fig. 7, it was confirmed that the thickness of the SiCN film formed per cycle in Sample 3 was thicker than the thicknesses of the SiCN films formed per cycle in Samples 1 and 2. This indicates that Sample 3 can achieve the highest cycle rate.

[0135] As shown in Figure 7, the composition ratio of Si in the SiCN film was the same for all samples. It was confirmed that the composition ratio of N was the lowest in Sample 3 and the highest in Sample 2. It was confirmed that the composition ratio of C was the highest in Sample 3 and the lowest in Sample 2. That is, it was confirmed that the composition ratio of C in Sample 3 was significantly higher than that of the other samples, without substantially changing the composition ratio of Si from that of the other samples. [Explanation of symbols]

[0136] 200 wafers

Claims

1. (a) supplying a first gas containing a first element and a halogen element to a substrate; (b) supplying a second gas containing a second element different from the first element and hydrogen to the substrate; (c) supplying a plasma-excited hydrogen-containing gas different from the second gas to the substrate; (d) supplying a third gas containing a third element different from the first element and the second element to the substrate; and (c) is performed a predetermined number of times after (a) and (b) and before (d), thereby forming a film containing the first element, the second element, and the third element on the substrate.

2. 2. The substrate processing method according to claim 1, wherein the second gas contains at least one of carbon and boron as the second element.

3. 2. The substrate processing method according to claim 1, wherein the third element is nitrogen.

4. 2. The substrate processing method according to claim 1, wherein the third gas is a gas containing nitrogen and hydrogen.

5. 2. The substrate processing method according to claim 1, wherein in (d), the third gas is supplied to the substrate without plasma.

6. 2. The substrate processing method according to claim 1, wherein the hydrogen-containing gas is a nitrogen-free gas.

7. (a) supplying the first gas to the substrate through a first nozzle; 7. The substrate processing method according to claim 6, wherein in (c), the hydrogen-containing gas is supplied to the substrate via a second nozzle different from the first nozzle, and the hydrogen-containing gas is supplied to the first nozzle.

8. 2. The substrate processing method according to claim 1, wherein in (c), supply of the hydrogen-containing gas to the substrate is started before plasma excitation of the hydrogen-containing gas is started.

9. 2. The substrate processing method according to claim 1, wherein the first gas is a gas containing hydrogen.

10. The substrate processing method according to claim 1 , wherein the first element is a metal element or a metalloid element.

11. 2. The substrate processing method according to claim 1, wherein the first gas does not contain the second element.

12. 2. The substrate processing method according to claim 1, further comprising: (e) between (c) and (d), a step of not supplying the hydrogen-containing gas and the third gas and evacuating a space in which the substrate is present.

13. 2. The substrate processing method according to claim 1, further comprising: (f) between (a) and (b), a step of stopping the supply of the first gas and the second gas and evacuating a space in which the substrate exists.

14. 2. The substrate processing method according to claim 1, wherein in (c), the halogen element bonded to the first element is removed from the layer containing the first element and the second element formed in (b), thereby forming a dangling bond of the first element.

15. 2. The substrate processing method according to claim 1, wherein in (c), hydrogen bonded to the second element is desorbed from the layer containing the first element and the second element formed in (b), thereby forming dangling bonds of the second element.

16. The ratio of the second element contained in the film containing the first element, the second element, and the third element is 2. The substrate processing method according to claim 1, wherein the ratio of the second element contained in the film formed by performing a cycle including (a), (b), and (d) but not including (c) is greater than the ratio of the second element contained in the film formed by performing a cycle including (a), (b), and (d) but not including (c).

17. The ratio of the second element contained in the film containing the first element, the second element, and the third element is 2. The substrate processing method according to claim 1, wherein the ratio of the second element contained in a film formed by performing a cycle including steps (a), (b), (c), and (d), in which step (c) is performed after step (d), is greater than the ratio of the second element contained in the film formed by performing a cycle including steps (a), (b), (c), and (d)

18. (a) supplying a first gas containing a first element and a halogen element to a substrate; (b) supplying a second gas containing a second element different from the first element and hydrogen to the substrate; (c) supplying a plasma-excited hydrogen-containing gas different from the second gas to the substrate; (d) supplying a third gas containing a third element different from the first element and the second element to the substrate; and performing a predetermined number of cycles in which (c) is performed after (a) and (b) and before (d), A method for manufacturing a semiconductor device, comprising forming a film containing the first element, the second element, and the third element on the substrate.

19. (a) supplying a first gas containing a first element and a halogen element to a substrate; (b) supplying a second gas containing a second element different from the first element and hydrogen to the substrate; (c) supplying a plasma-excited hydrogen-containing gas different from the second gas to the substrate; (d) supplying a third gas containing a third element different from the first element and the second element to the substrate; and performing a predetermined number of cycles in which (c) is performed after (a) and (b) and before (d), forming a film containing the first element, the second element, and the third element on the substrate, A program executed by a computer in a substrate processing apparatus.

20. a first gas supply system that supplies a first gas containing a first element and a halogen element to the substrate; a second gas supply system that supplies a second gas containing a second element different from the first element and hydrogen to the substrate; a hydrogen-containing gas supply system including a plasma excitation unit that plasma-excites a hydrogen-containing gas different from the second gas, and that supplies the plasma-excited hydrogen-containing gas to the substrate; a third gas supply system that supplies a third gas containing a third element different from the first element and the second element to the substrate; a control unit configured to be capable of controlling the first gas supply system, the second gas supply system, the hydrogen-containing gas supply system, and the third gas supply system to perform a process of forming a film containing the first element, the second element, and the third element on the substrate by performing a cycle of (a) supplying the first gas to the substrate, (b) supplying the second gas to the substrate, (c) supplying the plasma-excited hydrogen-containing gas to the substrate, and (d) supplying the third gas to the substrate a predetermined number of times, the cycle including performing (c) after (a) and (b) and before (d); A substrate processing apparatus comprising:

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